382 results on '"G. Abreu"'
Search Results
152. Influência da temperatura e do teor de humidade do solo na área foliar e acumulação de matéria seca durante o estabelecimento da ervilha, do milho e do girassol Influence of temperature and soil moisture on leaf area and dry matter accumulation during establishment of pea, maize and sunflower
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J. A. Andrade and F. G. Abreu
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lcsh:Agriculture ,lcsh:S - Abstract
O crescimento foliar e a acumulação de matéria seca durante o estabelecimento da ervilha (Pisum sativum L., var. Ballet), do milho (Zea mays L., var. Lorena) e do girassol (Helianthus annuus L., var. Flora-sol) foram estudados em função da temperatura e do teor de água num solo Pmg(Évora) e num Cb (Lisboa), entre Junho de 1995 e Novembro de 1996. Mediu-se a temperatura do solo a 2 e 4 cm de profundidade, a temperatura do ar e a humidade do solo. A área foliar das plântulas foi estimada a partir de medições do comprimento e da largura de cada folha. A acumulação de matéria seca foi avaliada pela pesagem da parte aérea das plântulas após secagem em estufa. Os dados foram analisados com base no conceito de tempo térmico. Para teores de humidade superiores a 50% da capacidade utilizável de cada solo, a área foliar durante o estabelecimento da ervilha e do milho aumentou linearmente com a temperatura acumulada, enquanto que a do girassol aumentou exponencialmente durante o mesmo período. A relação entre a acumulação de matéria seca de qualquer das culturas e a temperatura acumulada foi exponencial. O tipo de solo influenciou significativamente o “início da expansão foliar” da ervilha e do girassol, a “taxa térmica de expansão foliar” do milho e a acumulação de matéria seca da ervilha e do milho. O “início da expansão foliar” da ervilha ocorreu mais cedo no solo Cb enquanto que o do girassol ocorreu mais cedo no solo Pmg. A expansão foliar do milho foi mais rápida no solo Pmg. A acumulação de matéria seca da ervilha foi mais rápida no solo Cb, enquanto que a do girassol foi mais rápida no solo Pmg. Em ambos os solos, baixos teores de humidade afectaram negativamente a expansão da área foliar e a acumulação de matéria seca.Leaf area expansion and accumulation of dry matter during the establishment of pea (Pisum sativum L., var. Ballet), maize (Zea mays L., var. Lorena) and sunflower (Helianthus annuus L., var. Florasol) were studied at different temperatures and soil moisture contents in a Vertisol (Lisboa)and a Luvisol (Évora) from June 1995 to November 1996. Measurements were made of soil temperature at 2 and 4 cm depth, air temperature and soil water content. Leaf area per plant was estimated from measurements of the length and width of each leaf. Above ground seedling dry matter was weighed after oven drying. Data analysis was based on the thermal time concept. For water contents above 50% of the available capacity of each soil, leaf area of pea and maize increased linearly with accumulated temperature while that of sunflower increased exponentially. Dry matter of all crops increased exponentially with accumulated temperature. Significant differences between the two types of soil were found on the “initiation of leaf area expansion” of pea and sunflower, on the “thermal-rate for leaf area expansion” of maize and on the dry matter accumulation of pea and maize seedlings. The “initiation of leaf expansion” of pea occurred earlier in soil Cb while that of sunflower occurred earlier in soil Pmg. Leaf area expansion of maize was faster in soil Pmg. Dry matter accumulation of pea was faster in soil Cb while that of sunflower was faster in soil Pmg. In both soils, low soil water contents reduced leaf area expansion and dry matter accumulation of the crops.
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- 2007
153. Tuberculosis en niños de 0-14 años: Cuba, 1994-2003
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E. Gonzalez Ochoa, MªJ Llanes Cordero, J D'fana Valdés, S. Borroto Gutiérrez, G. Abreu Suárez, J. González Valdés, and L. Armas Pérez
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Geography ,Surveillance ,Pediatrics, Perinatology and Child Health ,Control ,Trend ,Tuberculosis ,Cuba ,Infant newborn ,Humanities ,Children ,Pediatrics ,RJ1-570 ,West indies - Abstract
Introducción: La ocurrencia de tuberculosis en niños es un signo de transmisión continua de la infección. En este estudio describimos la distribución y tendencia de las tasas de incidencia de casos nuevos de tuberculosis de niños menores de 15 años de edad en Cuba. Métodos: Se estimaron las tasas de incidencia y su tendencia, por provincias y grupos de edades del período 1994-2003. Se determinó la distribución porcentual, porcentaje de variación global y promedio anual de las tasas, así como las tasas y porcentajes de tuberculosis según su localización. Resultados: La tasa de incidencia disminuyó de 0,76 × 105 en 1994 a 0,31 en 2003 (59,2 % reducción global y 6,6 % reducción anual como promedio). En 1995 se notificó la tasa más alta 1,06 × 105 (26 casos). En casi todas las provincias la tendencia de la incidencia fue descendente, excepto en Ciudad Habana, Sancti Spíritus, Santiago de Cuba e Isla de la Juventud. El 69,6 % de la tuberculosis infantil fue de localización pulmonar. Los grupos de edades de 10-14 años (35,6 %) y 1-4 (35,2%) presentaron los porcentajes más altos dentro de la población infantil afectada. Conclusiones: La tuberculosis es muy poco frecuente y más bien rara en menores de un año y en general presenta notificación muy baja en todo el país con una tendencia global descendente mantenida. : Introduction: Tuberculosis in infants and children is a sign of continuous transmission. The present article describes the distribution and the trend in incidence rates of new tuberculosis cases in 0-15-year-olds in Cuba. Methods: Incidence rates and their trend were estimated by provinces and age groups for the 1994-2003 period. Distribution and overall variation percentages, annual average rates, and rates and percentages according to classification were determined. Results: The incidence rate decreased from 0.76 × 105 in 1994 to 0.31 in 2003 (59.2 % of the overall reduction and 6.6 % of the annual average reduction). The highest rate (1.06 × 105) was found in 1995 (26 cases). In almost all provinces, the incidence trend decreased, except in the City of Havana, Sancti Spíritus, Santiago de Cuba, and the Isle of Youth. Childhood tuberculosis was mainly pulmonary (69.6 %). Among the affected population, the highest percentages were found in the groups aged 10-14 years (35.6%) and 1-4 years (35.2%). Conclusions: Tuberculosis is infrequent and is extremely uncommon in infants. Notification is low throughout the country and the overall trend shows a steady decrease.
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- 2007
154. Estudo anatômico do trajeto do canal mandibular em felinos (Felis catus domesticus)
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Marcelo Ismar Silva Santana, A. R. L. Silva, L. G. Abreu, Paula Diniz Galera, Samuel Carvalho Cotrim, and João Ricardo Bielefeld Nardotto
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Molar ,General Veterinary ,business.industry ,Mandíbula ,cats ,Mandible ,Mandibular canal ,Mandibular foramen ,Anatomy ,tomography ,Gato ,Mandibular first molar ,Mental foramen ,canal mandibular ,medicine.anatomical_structure ,gatos ,mandibular canal ,tomografia ,medicine ,Premolar ,lcsh:Animal culture ,Mandibular lateral incisor ,business ,lcsh:SF1-1100 - Abstract
Objetivou-se descrever, por meio de tomografia computadorizada, o trajeto do canal mandibular (CM) em 20 gatos sem raça definida, com ausência de alterações na cavidade oral, provenientes do Centro de Controle de Zoonoses do Distrito Federal. Foram realizados cortes tomográficos com 2mm de espessura, acompanhando todo o trajeto do CM, tendo como referência a região do forame mandibular, as raízes distais e mesiais dos dentes pré-molares e molares e o forame mentoniano, obtendo-se medidas desde o CM até as faces vestibular, lingual, ventral e alveolar (profundidade) do corpo da mandíbula, bem como seu diâmetro. Pôde constatar que o CM manteve-se no aspecto lingual do corpo da mandíbula desde o forame mandibular até a raiz mesial do 1º pré-molar, onde se deslocou para a face vestibular, emergindo no forame mentoniano. Com relação à profundidade, seu trajeto sofreu declive a partir do forame mandibular até a região da raiz mesial do 1º molar, onde alcançou seu ponto mais profundo para prosseguir em suave ascensão até o forame mentoniano. Os dados apresentados contribuem para o estudo anatômico da mandíbula de gatos, bem como auxiliam no melhor planejamento e execução de procedimentos cirúrgicos na mandíbula dessa espécie. ABSTRACT This study aimed to describe the path of the mandibular canal (MC), using computerized tomography, in twenty mongrel cats, with no changes in the oral cavity, from the Zoonosis Control Center of the Federal District. 2mm thick tomographic sections were taken following the entire path of the mandibular canal, considering as reference the region of the mandibular foramen, the distal and mesial roots of premolar and molar teeth, and mental foramen, obtaining measurements from the MC until the buccal, lingual, ventral and alveolar (depth) surfaces of the mandibular body as well as its diameter. MC remained on the lingual aspect of the mandibular body from the mandibular foramen to the mesial root of the first premolar, where it displaced to the buccal surface, emerging from the mental foramen. Regarding the depth, we observed a downward path from the mandibular foramen to the mesial root of the first premolar, where it reached its deepest point, the path continued in gentle ascent until to the mental foramen. Our data contribute to the anatomical study of the feline jaw and allow a better planning and execution of surgical procedures in the mandible of this species.
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- 2015
155. Developmental aspects of the direct-developing frog Adelophryne maranguapensis
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Ana V P, de Lima, Alice H, Reis, Nathália G, Amado, Daniel, Cassiano-Lima, Diva M, Borges-Nojosa, Reinaldo B, Oriá, and José G, Abreu
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Embryo, Nonmammalian ,Oocytes ,Animals ,Embryonic Development ,Extremities ,Anura ,Skin - Abstract
Direct development in amphibians is characterized by the loss of aquatic breeding. The anuran Adelophryne maranguapensis is one example of a species with direct development, and it is endemic to the state of Ceará, Brazil. Detailed morphological features of A. maranguapensis embryos and the stages of sequential development have not been described before. Here, we analyzed all available genetic sequence tags in A. maranguapensis (tyr exon 1, pomc and rag1) and compared them with sequences from other species of Adelophryne frogs. We describe the A. maranguapensis reproductive tract and embryonic body development, with a focus on the limbs, tail, ciliated cells of the skin, and the egg tooth, which were analyzed using scanning electron microscopy. Histological analyses revealed ovaries containing oocytes surrounded by follicular cells, displaying large nuclei with nucleoli inside. Early in development, the body is unpigmented, and the neural tube forms dorsally to the yolk vesicle, typical of a direct-developing frog embryo. The hindlimbs develop earlier than the forelimbs. Ciliated cells are abundant during the early stages of skin development and are less common during later stages. The egg tooth appears in the later stages and develops as a keratinized microridge structure. The developmental profile of A. maranguapensis presented here will contribute to our understanding of the direct-development model and may help preserve this endangered native Brazilian frog. genesis 54:257-271, 2016. © 2016 Wiley Periodicals, Inc.
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- 2015
156. Connective-Tissue Growth Factor (CTGF/CCN2) Induces Astrogenesis and Fibronectin Expression of Embryonic Neural Cells In Vitro
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Vivaldo Moura Neto, Alice H. Reis, Luiz Gustavo Dubois, Laís S. S. Ferreira, Hervé Chneiweiss, Luciana Romão, Juliana M. Coelho Aguiar, Fabio A. Mendes, José G. Abreu, Suzana Assad Kahn, Plasticité gliale et neuro-oncologie = Glial Plasticity (NPS-04), Neuroscience Paris Seine (NPS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Biologie Paris Seine (IBPS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Biologie Paris Seine (IBPS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ), Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Programa de Nucleos de Excelencia (PRONEX), Neurosciences Paris Seine (NPS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Biologie Paris Seine (IBPS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Biologie Paris Seine (IBPS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Biologie Paris Seine (IBPS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Biologie Paris Seine (IBPS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
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MAP Kinase Signaling System ,Cellular differentiation ,medicine.medical_treatment ,lcsh:Medicine ,Xenopus Proteins ,Nestin ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Cell Line, Tumor ,Glial Fibrillary Acidic Protein ,medicine ,Animals ,Humans ,Phosphorylation ,lcsh:Science ,Cells, Cultured ,030304 developmental biology ,Gliogenesis ,Cerebral Cortex ,0303 health sciences ,Multidisciplinary ,Mitogen-Activated Protein Kinase 3 ,biology ,integumentary system ,Growth factor ,SOXB1 Transcription Factors ,lcsh:R ,Wnt signaling pathway ,Connective Tissue Growth Factor ,Cell Differentiation ,Recombinant Proteins ,Cell biology ,Fibronectins ,Neoplasm Proteins ,Fibronectin ,CTGF ,Gene Expression Regulation ,CYR61 ,Astrocytes ,biology.protein ,lcsh:Q ,[SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] ,Stem cell ,Glioblastoma ,Protein Processing, Post-Translational ,030217 neurology & neurosurgery ,Cell Division ,Research Article - Abstract
Connective-tissue growth factor (CTGF) is a modular secreted protein implicated in multiple cellular events such as chondrogenesis, skeletogenesis, angiogenesis and wound healing. CTGF contains four different structural modules. This modular organization is characteristic of members of the CCN family. The acronym was derived from the first three members discovered, cysteine-rich 61 (CYR61), CTGF and nephroblastoma overexpressed (NOV). CTGF is implicated as a mediator of important cell processes such as adhesion, migration, proliferation and differentiation. Extensive data have shown that CTGF interacts particularly with the TGFβ, WNT and MAPK signaling pathways. The capacity of CTGF to interact with different growth factors lends it an important role during early and late development, especially in the anterior region of the embryo. ctgf knockout mice have several cranio-facial defects, and the skeletal system is also greatly affected due to an impairment of the vascular-system development during chondrogenesis. This study, for the first time, indicated that CTGF is a potent inductor of gliogenesis during development. Our results showed that in vitro addition of recombinant CTGF protein to an embryonic mouse neural precursor cell culture increased the number of GFAP- and GFAP/Nestin-positive cells. Surprisingly, CTGF also increased the number of Sox2-positive cells. Moreover, this induction seemed not to involve cell proliferation. In addition, exogenous CTGF activated p44/42 but not p38 or JNK MAPK signaling, and increased the expression and deposition of the fibronectin extracellular matrix protein. Finally, CTGF was also able to induce GFAP as well as Nestin expression in a human malignant glioma stem cell line, suggesting a possible role in the differentiation process of gliomas. These results implicate ctgf as a key gene for astrogenesis during development, and suggest that its mechanism may involve activation of p44/42 MAPK signaling. Additionally, CTGF-induced differentiation of glioblastoma stem cells into a less-tumorigenic state could increase the chances of successful intervention, since differentiated cells are more vulnerable to cancer treatments.
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- 2015
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157. MASE-BDI: Agents with Practical Reasoning for Land Use and Cover Change Simulation
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Célia Ghedini Ralha, Cassio G. C. Coelho, and Carolina G. Abreu
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Practical reason ,Land use ,business.industry ,Computer science ,Environmental resource management ,Cover (algebra) ,business - Abstract
Agents with a cognitive dimension are paramount to represent and understand land use and land cover changes that involves decision making. A Belief-Desire-Intention(BDI)-Agent system for environmental simulation was developed:the MASE-BDI framework. MASE-BDI, a novel version of MASE, implements agents that can be represented by their individual beliefs and in- tentional behavior to choose plans of action in a complex environment. We investigate the advantages, limitations and drawbacks of this new design and how practical reasoning agents can contribute to decision support for sustain- ability. Experiments were made in a spatially explicit LUCC study case of the Brazilian Cerrado between the years of 2002 and 2008. MASE-BDI simulation results were compared to those obtained with the multi-agent system for land- use change simulation previously developed in this research project.
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- 2015
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158. Reproduction of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) B biotype in maize fields (Zea mays L.) in Brazil
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Eliane D, Quintela, Aluana G, Abreu, Julyana F Dos S, Lima, Gabriel M, Mascarin, Jardel B Dos, Santos, and Judith K, Brown
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Hemiptera ,Oviposition ,Reproduction ,Animals ,Agriculture ,Herbivory ,Sequence Analysis, DNA ,Zea mays ,Brazil - Abstract
Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) was observed to have completed its reproductive cycle from the egg to the adult on maize (Zea mays L.). Field and screenhouse studies were carried out to investigate the durability of this putative and unprecedented adaptation to a grass host.Analysis of the mitochondrial COI gene sequence identified the maize-associated B. tabaci as the exotic B biotype (major clade North Africa-Mediterranean-Middle East). Results showed that whiteflies migrated from soybean crops and successfully established in maize plants. Females exhibited a preference for oviposition primarily on the first and second leaves of maize, but were also able to colonise developing leaves. A high, natural infestation on maize (193.3 individuals, all developmental stages) was observed within a 7.1 cmThis is the first report of the B biotype completing its development on maize plants. This surprising anomaly indicates that the B biotype is capable of adapting to monocotyledonous host plants, and importantly, broadens the host range to include at least one species in the Poaceae. © 2016 Society of Chemical Industry.
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- 2015
159. Interactive properties of human glioblastoma cells with brain neurons in culture and neuronal modulation of glial laminin organization
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José G. Abreu, Christina Maeda Takiya, Jorge Marcondes de Souza, Giselle Pinto de Faria, Leila Chimelli, Fabio A. Mendes, Rosenilde Hollanda, Vivaldo Moura Neto, Sheila Cristina de Souza Martins, Verônica Morandi, Tercia Alves, Luciana Romão, and Jane Cristina de Oliveira Faria
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Cancer Research ,Neurite ,Central nervous system ,Biology ,Extracellular matrix ,Laminin ,Glioma ,Neurites ,medicine ,Animals ,Humans ,Rats, Wistar ,Molecular Biology ,Cells, Cultured ,Neurons ,Brain Neoplasms ,Brain ,Cell Differentiation ,Cell Biology ,medicine.disease ,Embryonic stem cell ,Rats ,Cell biology ,Neuroepithelial cell ,medicine.anatomical_structure ,nervous system ,Astrocytes ,Immunology ,biology.protein ,Neuron ,Glioblastoma ,Developmental Biology - Abstract
The harmonious development of the central nervous system depends on the interactions of the neuronal and glial cells. Extracellular matrix elements play important roles in these interactions, especially laminin produced by astrocytes, which has been shown to be a good substrate for neuron growth and axonal guidance. Glioblastomas are the most common subtypes of primary brain tumors and may be astrocytes in origin. As normal laminin-producing glial cells are the preferential substrate for neurons, and glial tumors have been shown to produce laminin, we questioned whether glioblastoma retained the same normal glial–neuron interactive properties with respect to neuronal growth and differentiation. Then, rat neurons were co-cultured onto rat normal astrocytes or onto three human glioblastoma cell lines obtained from neurosurgery. The co-culture confirmed that human glioblastoma cells as well as astrocytes maintained the ability to support neuritogenesis, but non-neural normal or tumoral cells failed to do so. However, glioblastoma cells did not distinguish embryonic from post-natal neurons in relation to neurite pattern in the co-cultures, as normal astrocytes did. Further, the laminin organization on both normal and tumoral glial cells was altered from a filamentous arrangement to a mixed punctuate/filamentous pattern when in co-culture with neurons. Together, these results suggest that glioblastoma cells could identify neuronal cells as partners, to support their growth and induce complex neurites, but they lost the normal glia property to distinguish neuronal age. In addition, our results show for the first time that neurons modulate the organization of astrocytes and glioblastoma laminin on the extracellular matrix.
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- 2006
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160. ASSESSMENT OF CHESTNUT INK DISEASE SPREAD BY GEOSTATISTICAL METHODS
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C. G. Abreu, F. W. Macedo, C. P. Marques, and L. M. Martins
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Alternative methods ,Geography ,Aerial photography ,biology ,Kriging ,High spatial resolution ,Sampling (statistics) ,Lower cost ,Spatial variability ,Horticulture ,Phytophthora cinnamomi ,biology.organism_classification ,Cartography - Abstract
Chestnut ink disease of chestnut associated with the soil-borne pathogen Phytophthora cinnamomi Rands, is observed in single trees as rarefied foliage and general dieback which begins at the branch tips. These conditions can be detected by satellite images with high spatial resolution or by large format aerial photography. However, capturing those images frequently over small sampling areas is very expensive. This study presents an alternative method to evaluate chestnut health using lower cost technology: Small Format Aerial Photography (SFAP), of ground plots taken from light aircrafts. Normal colour and infrared SFAP from 2000 and 2001 were compared with on-the-ground evidence of chestnut ink disease. The spatial variability of health conditions of chestnut plots was adjusted in experimental semivariograms, using a spherical model. The spread of ink disease was then interpolated by ordinary kriging. Different vegetative conditions were detected using SFAP, in 2000 and 2001, showing, respectively, 5.6% and 11.1% of dead chestnut trees. The geostatistical interpolation of the study area (460 ha) found a critical cluster where chestnut decline had increased.
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- 2005
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161. DIAGNOSIS OF INK DISEASE OF CHESTNUT BY MOLECULAR IDENTIFICATION OF ASSOCIATED PHYTOPHTHORA SPECIES
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A. Choupina, V. Coelho, C. G. Abreu, Enrique Monte, Rosa Hermosa, and M. E. Gouveia
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P. cambivora ,Disease ,Horticulture ,Biology ,biology.organism_classification ,law.invention ,Microbiology ,ITS-RFLP identification ,DNA profiling ,Genetic marker ,law ,Phytophthora ,P. cinnamomi ,Gene ,Phytophthora detection ,Polymerase chain reaction ,Molecular identification - Abstract
For diagnostic proposes of ink disease, chestnut orchards with symptoms of decline or sudden death of trees were sampled by soil baiting techniques and selective agar media (P10VPH). Thirty-six Phytophthora isolates were obtained. One isolate per tree and three or two isolates from the soil of the same plant were considered for molecular identification. Genomic DNA was extracted from all the isolates and from the reference strain P. cinnamomi CECT 2965. The ribosomal regions ITS1, 5.8S and ITS2 were amplified with the universal primer pair ITS6 (Cooke and Duncan, 1997) and ITS4 (White et al., 1990) by PCR. The amplified fragment (900 pb) was digested with restriction enzymes MspI, AluI and TaqI. Two different patterns of fingerprinting were obtained with enzymes TaqI and AluI (type I and II) and three different patterns with MspI (type I, Ia, II). The fingerprinting of each isolate was compared with database of CABI by public web access. Type I and Ia (14 isolates) were assigned to P. cinnamomi and type II (4 isolates) was assigned to P. cambivora. Molecular methods provide a rapid means of Phytophthora species identification associated with ink disease of chestnut and will provide a useful tool for etiological and epidemiological studies of this important disease of chestnut.
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- 2005
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162. Extended-spectrum β-lactamase-producing enterobacteriaceae in community-acquired urinary tract infections in São Luís, Brazil
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Sirlei Garcia Marques, Azizedite Guedes Gonçalves, Afonso G. Abreu, and Valério Monteiro-Neto
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Antibiotic resistance ,biology ,Enterobacteriaceae Infections ,Urinary system ,Urine ,biology.organism_classification ,Microbiology ,Enterobacteriaceae - Abstract
The number of ESBL-producing Enterobacteriaceae in community-acquired urinary tract infections worldwide is probably underestimated because of the technical difficulties encountered with their detection. In this study, out of 5,672 urine samples analyzed, 916 were positive for uropathogens, 472 of them being enterobacteria of which 7.6% produced β-lactamases. Analysis of the isolated from 36 patients showed a high level of antibiotic resistance, with 52.7% and 80.5% of isolates expressing blaTEM and blaCTX-M, respectively.
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- 2013
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163. Soil compaction and chestnut ink disease
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Teresa Fonseca, Bernard R. Parresol, and C. G. Abreu
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Ecology ,Forest pathology ,Soil compaction ,Forestry ,Biology - Abstract
Summary Chestnut ink disease caused by the oomycete Phytophthora cinnamomi, a soil-borne pathogen of world-wide distribution, accounts for the majority of disease problems on chestnuts in Portugal, limiting yield in a large number of stands and impeding establishment of trees in new areas. A survey was carried out in 32 chestnut stands in the Padrela Mountains of northern Portugal to investigate the relationship among ink disease occurrence, edaphic factors and management practices. A logistic regression function was employed to analyze the effect of soil attributes and management practices on the stand health status. Results showed that the main factors affecting disease were soil compaction (COMP), soil organic matter level (OM) and manuring practice (MA). A logistic model containing the soil variable COMP and the interaction term OM × MA correctly predicted the stand health status in 94%, or 30, of the 32 stands studied. The logistic function coefficients indicate that the probability of a stand having ink disease increases with increasing soil compaction and increasing soil organic matter content in stands where manuring is the usual practice. Resume La maladie de l'encre du châtaignier, causee par l'oomycete Phytophthora cinnamomi, pathogene du sol ayant une distribution mondiale, est la cause des principaux problemes sanitaires des châtaigniers au Portugal, limitant la production dans de nombreux peuplements et l’etablissement de plantations dans de nouvelles zones. Une enquete a ete menee dans 32 peuplements de châtaigniers des Montagnes Padrela, dans le nord du Portugal, pour etudier la relation entre maladie de l'encre, facteurs edaphiques et pratiques de gestion. La regression logistique a ete utilisee pour analyser les effets des variables liees au sol et aux pratiques de gestion sur le statut sanitaire des peuplements. Il en resulte que les principaux facteurs affectant la maladie sont la compaction du sol (COMP), le niveau de matiere organique du sol (OM) et les pratiques de fertilisation organique (MA). Un modele logistique comprenant la variable COMP et l'interaction OMxMA predit correctement le statut sanitaire du peuplement dans 94% des cas, soit 30 sur 32 des parcelles etudiees. Les coefficients de la fonction logistique indiquent que la probabilite pour un peuplement d’etre atteint par la maladie de l'encre augmente avec la compaction du sol et le niveau de matiere organique dans les peuplements ou la fertilisation organique est une pratique courante. Zusammenfassung Der Oomyzet Phytophthora cinnamomi ist ein bodenburtiges Pathogen mit weltweiter Verbreitung. Es ist fur die Mehrheit der Erkrankungen von Edelkastanien in Portugal verantwortlich. Der Pilz reduziert den Ertrag in vielen Bestanden und verunmoglicht die Bestandesgrundung. In 32 Bestanden von Edelkastanien in den Padrela-Bergen im Norden Portugals wurden die Zusammenhange zwischen dem Vorkommen der Tintenkrankheit, edaphischen Faktoren und Bewirtschaftungsformen untersucht. Die Auswirkungen von Bodenfaktoren und Bewirtschaftungsformen auf den Gesundheitszustand der Bestande wurden mittels einer logistischen Regression analysiert. Verantwortlich fur das Auftreten der Krankheit waren hauptsachlich die Bodenverdichtung, der Anteil an organischem Material im Boden und das Ausbringen von Jauche. Das logistische Model mit der Bodenverdichtung und der Interaktion zwischen dem Anteil an organischem Material im Boden und dem Ausbringen von Jauche als unabhangige Variabeln erlaubte die beste Vorhersage des Gesundheitszustandes der Bestande. Fur 94% oder 30 der 32 Bestande war die Vorhersage des Gesundheitszustandes korrekt. Die Regressionskoeffizienten zeigten, dass die Wahrscheinlichkeit fur das Vorkommen der Krankheit in einem Bestand mit zunehmender Bodenverdichtung und zunehmendem Anteil organischen Materials in gejauchten Bestanden zunimmt.
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- 2004
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164. Effect of Chestnut Ink Disease on Photosynthetic Performance
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M. Pimentel-Pereira, J. Araújo‐Alves, José Gomes-Laranjo, J.M.G. Torres-Pereira, C. G. Abreu, and J. Ferreira-Cardoso
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Chlorophyll b ,Chlorophyll a ,Stomatal conductance ,Physiology ,food and beverages ,Plant Science ,Biology ,Phytophthora cinnamomi ,biology.organism_classification ,Photosynthesis ,Fagaceae ,chemistry.chemical_compound ,Horticulture ,chemistry ,Chlorophyll ,Botany ,Genetics ,Agronomy and Crop Science ,Transpiration - Abstract
In order to evaluate the evolutionary impact of chestnut ink disease, infected trees (cv. Judia), were compared with non-infected trees, in three separate months: July, September and October. The aim of this work is to analyse the effects of the infection using parameters related to plant water relations, gas exchange and biometric data of leaves and fruits. In this period, temperatures decreased from 31 to 16°C contrarily to precipitation, which increased from 18 to 178 mm, respectively. In consequence, leaf water potential changed between -1.6 and -1.0 MPa while in infected plants the values maintained around -1.2 MPa over the referred period. Nevertheless, at the gas exchanges level, differences in stomatal conductance, transpiration and photosynthesis were only detected in October. Concerning photosynthesis rate, the infected plants showed, in relation to September, a reduction around 35% whereas in non-infected plants the decline was 25%. Alterations in the chlorophyll contents were also observed between September and October. In infected plants reduction on total amount of chlorophyll was from 18.6 to 13.4 mg/W f , while in non-infected plants values were only decayed from 15.1 to 13.1 mg/W f . In relation to chlorophyll a/chlorophyll b ratio, plants infected by the oomycete preserved values in the level of 2.6, whereas in healthy plants values changed from 2.5 to 2.3. Leaves and fruits from infected chestnut trees were 13 and 20% smaller, respectively than those from non-infected. Fruits from infected plants also had less starch but more crude protein.
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- 2004
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165. A quantitative comparison on multihop algorithms
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SEVERI, STEFANO, DARDARI, DAVIDE, G. Abreu, S. Severi, G. Abreu, and D. Dardari
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WIRELESS NETWORKS ,LOCALIZATION ,MULTI-HOP - Abstract
Multihop Localization Algorithms (MLAs) are an efficient alternative to traditional message-passing methods in multihop wireless networks in terms of communication costs, robustness to mobility and location privacy to end users. However MLAs are accurate only under particular network conditions (high number of anchor nodes, isotropic topologies, etc . . . ) therefore up to now they have not been widely used. In this paper we analyze the causes of this behaviour through a comparison of different schemes. We therefore introduce a new MLA based on Semidefinite Programming (SDP) which results to be highly robust when inaccurate range information are present.
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- 2010
166. Isoquercitrin suppresses colon cancer cell growth in vitro by targeting the Wnt/β-catenin signaling pathway
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Danilo Predes, Barbara F. Fonseca, Fabio A. Mendes, José G. Abreu, Ana C. Dudenhoeffer, Débora M. Cerqueira, Nathalia G. Amado, Helena L. Borges, and Alice H. Reis
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Beta-catenin ,Embryo, Nonmammalian ,Xenopus ,Cell ,Blotting, Western ,Active Transport, Cell Nucleus ,Antineoplastic Agents ,Xenopus Proteins ,Biochemistry ,Cell Line ,Cell Movement ,Cell Line, Tumor ,medicine ,Animals ,Humans ,heterocyclic compounds ,Molecular Biology ,Wnt Signaling Pathway ,Early Growth Response Protein 2 ,In Situ Hybridization ,beta Catenin ,Body Patterning ,Cell Proliferation ,Cell Nucleus ,biology ,Cell growth ,Reverse Transcriptase Polymerase Chain Reaction ,fungi ,Wnt signaling pathway ,LRP6 ,food and beverages ,Gene Expression Regulation, Developmental ,LRP5 ,Cell Biology ,biology.organism_classification ,HCT116 Cells ,Immunohistochemistry ,Cell biology ,carbohydrates (lipids) ,medicine.anatomical_structure ,Colonic Neoplasms ,biology.protein ,Quercetin ,Signal transduction ,Lithium Chloride - Abstract
Flavonoids are plant-derived polyphenolic molecules that have potential biological effects including anti-oxidative, anti-inflammatory, anti-viral, and anti-tumoral effects. These effects are related to the ability of flavonoids to modulate signaling pathways, such as the canonical Wnt signaling pathway. This pathway controls many aspects of embryonic development and tissue maintenance and has been found to be deregulated in a range of human cancers. We performed several in vivo assays in Xenopus embryos, a functional model of canonical Wnt signaling studies, and also used in vitro models, to investigate whether isoquercitrin affects Wnt/β-catenin signaling. Our data provide strong support for an inhibitory effect of isoquercitrin on Wnt/β-catenin, where the flavonoid acts downstream of β-catenin translocation to the nuclei. Isoquercitrin affects Xenopus axis establishment, reverses double axes and the LiCl hyperdorsalization phenotype, and reduces Xnr3 expression. In addition, this flavonoid shows anti-tumoral effects on colon cancer cells (SW480, DLD-1, and HCT116), whereas exerting no significant effect on non-tumor colon cell (IEC-18), suggesting a specific effect in tumor cells in vitro. Taken together, our data indicate that isoquercitrin is an inhibitor of Wnt/β-catenin and should be further investigated as a potential novel anti-tumoral agent.
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- 2014
167. Reproducibility of first- and second-trimester uterine artery pulsatility index measured by transvaginal and transabdominal ultrasound
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A E G M T, Ferreira, F, Mauad Filho, P S G, Abreu, F M, Mauad, E, Araujo Júnior, and W P, Martins
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Adult ,Reproducibility of Results ,Gestational Age ,Ultrasonography, Doppler ,Ultrasonography, Prenatal ,Pregnancy Trimester, First ,Uterine Artery ,Cross-Sectional Studies ,Pregnancy ,Reference Values ,Pregnancy Trimester, Second ,Pulsatile Flow ,Humans ,Female ,Brazil - Abstract
To examine and compare the reproducibility of measurement of first- and second-trimester uterine artery pulsatility index (UtA-PI) using transabdominal (TAS) and transvaginal (TVS) ultrasound.This was an observational study including women ≥ 18 years of age, with a singleton pregnancy, in the first trimester (between 11 + 0 and 13 + 6 weeks' gestation) or second trimester (between 20 and 26 weeks' gestation). UtA-PI and angle of insonation were assessed by two observers (one with 15 and the other with 3 years of experience) using both TAS and TVS. The more experienced observer performed two scans alternated by the other observer. The acquisitions were completely independent and the observers were blinded to each other and to their own measurements. Reproducibility of the measurements by TVS and TAS was assessed using the concordance correlation coefficients (CCCs), intraclass correlation coefficients (ICCs) and limits of agreement (LoA).We analyzed data from 97 women in the first trimester and 96 in the second trimester. The mean ± SD UtA-PI was significantly higher when measured using TVS, compared with TAS, in both the first (1.60 ± 0.49 vs 1.52 ± 0.63, respectively; P = 0.03) and second (1.07 ± 0.33 vs 0.96 ± 0.32, respectively; P0.001) trimesters. The median angle of insonation was significantly lower when using TVS, compared with TAS, in both the first (8.0° (interquartile range (IQR), 2.5-16.3°) vs 12.5° (IQR, 2.5-20.0°), respectively; P = 0.04) and second (10.0° (IQR, 4.5-16.5°) vs 17.5° (IQR, 5.0-27.9°), respectively; P0.001) trimesters. Both ultrasound techniques had similar reproducibility: the intraobserver CCC ranged from 0.93 to 0.95 and the interobserver CCC ranged from 0.81 to 0.86; and the ICCs of both techniques were highly comparable (the intraobserver LoA was approximately ± 20-30% and the interobserver LoA was approximately ± 30-40%).When measuring UtA-PI, assessment by TVS provides higher values and better insonation angle compared with TAS. The reproducibility of the ultrasound methods in both first and second trimesters of pregnancy was comparable and should not be considered as good. Future studies examining technical improvements with the aim of increasing the reproducibility of this technique should be encouraged.
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- 2014
168. The Serine Protease Pic From Enteroaggregative Escherichia coli Mediates Immune Evasion by the Direct Cleavage of Complement Proteins
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Marcia Y. Kondo, Lourdes Isaac, Luiz Juliano, Afonso G. Abreu, Adriana Patricia Granados Martinez, Tatiana R. Fraga, Maria A. Juliano, Angela Silva Barbosa, Fernando Navarro-Garcia, and Waldir P. Elias
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endocrine system ,Virulence Factors ,Complement factor I ,medicine.disease_cause ,IMUNOPROTEINAS ,Microbiology ,Shigella flexneri ,medicine ,Escherichia coli ,Immunology and Allergy ,Humans ,Immune Evasion ,Serine protease ,biology ,Complement component 2 ,Escherichia coli Proteins ,Hydrolysis ,Serine Endopeptidases ,Complement System Proteins ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,Complement system ,Infectious Diseases ,Enteroaggregative Escherichia coli ,biology.protein ,MASP1 - Abstract
Enteroaggregative and uropathogenic Escherichia coli, Shigella flexneri 2a, and the hybrid enteroaggregative/Shiga toxin-producing E. coli strain (O104:H4) are important pathogens responsible for intestinal and urinary tract infections, as well as sepsis and hemolytic uremic syndrome. They have in common the production of a serine protease called Pic. Several biological roles for Pic have been described, including protection of E. coli DH5α from complement-mediated killing. Hereby we showed that Pic significantly reduces complement activation by all 3 pathways. Pic cleaves purified C3/C3b and other proteins from the classic and lectin pathways, such as C4 and C2. Cleavage fragments of C3, C4, and C2 were also observed with HB101(pPic1) culture supernatants, and C3 cleavage sites were mapped by fluorescence resonance energy transfer peptides. Experiments using human serum as a source of complement proteins confirmed Pic proteolytic activity on these proteins. Furthermore, Pic works synergistically with the human complement regulators factor I and factor H, promoting inactivation of C3b. In the presence of both regulators, further degradation of C3 α' chain was observed. Therefore, Pic may contribute to immune evasion of E. coli and S. flexneri, favoring invasiveness and increasing the severity of the disorders caused by these pathogens.
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- 2014
169. Clostridium difficile toxin A attenuates Wnt/β-catenin signaling in intestinal epithelial cells
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Gerly Anne de Castro Brito, Nathalia G. Amado, Barbara F. Fonseca, Bruno B Lima, Ronaldo A. Ribeiro, José G. Abreu, and Débora Moreira Lima
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Immunology ,Bacterial Toxins ,Clostridium difficile toxin A ,GTPase ,Biology ,Microbiology ,Proto-Oncogene Proteins c-myc ,Enterotoxins ,Western blot ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Intestinal Mucosa ,beta Catenin ,Reporter gene ,Cellular Microbiology: Pathogen-Host Cell Molecular Interactions ,medicine.diagnostic_test ,Wnt signaling pathway ,LRP5 ,Epithelial Cells ,Molecular biology ,Rats ,Blot ,Wnt Proteins ,Infectious Diseases ,Cell culture ,Parasitology ,Signal Transduction - Abstract
Clostridium difficile toxins A and B (TcdA and TcdB) are homologous glycosyltransferases that inhibit a group of small GTPases within host cells, but several mechanisms underlying their pathogenic activity remain unclear. In this study, we evaluated the effects of TcdA on the Wnt/β-catenin pathway, the major driving force behind the proliferation of epithelial cells in colonic crypts. IEC-6 and RKO cells stimulated with Wnt3a-conditioned medium were incubated with 10, 50, and 100 ng/ml of TcdA for 24 h, resulting in a dose-dependent inhibition of the Wnt signaling, as demonstrated by a T-cell factor (TCF) reporter assay. This was further confirmed by immunofluorescence staining for nuclear localization of β-catenin and Western blotting for β-catenin and c-Myc (encoded by a Wnt target gene). Moreover, our Western blot analysis showed a decrease in the β-catenin protein levels, which was reversed by z-VAD-fmk, a pan-caspase inhibitor. Nonetheless, TcdA was still able to inhibit the Wnt/β-catenin pathway even in the presence of z-VAD-fmk, lithium chloride (a GSK3β inhibitor), or constitutively active β-catenin, as determined by a TCF reporter assay. Furthermore, preincubation of RKO cells with TcdA for 12 h also attenuated Wnt3a-mediated activation of Wnt signaling, suggesting that inactivation of Rho GTPases plays a significant role in that inhibition. Taken together, these findings suggest that attenuation of the Wnt signaling by TcdA is important for TcdA antiproliferative effects.
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- 2014
170. A Model and Simulation Framework for Exploring Potential Impacts of Land Use Policies: The Brazilian Cerrado Case
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Bruno Macchiavello, Carolina G. Abreu, Cassio G. C. Coelho, and Célia Ghedini Ralha
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Sustainable development ,Decision support system ,Land use ,Social system ,Process (engineering) ,business.industry ,Computer science ,Multi-agent system ,Environmental resource management ,Sustainability ,Land-use planning ,business - Abstract
Land use and cover change (LUCC) research is important to support insightful management of Earth's land use to avoid irreversible damage. However, LUCC is a complex process that relates the interaction between natural and social systems at different temporal and spatial scales. Nevertheless, the representation of different interaction patterns through agent-based modeling and multi-agent systems can contribute to decision support for sustainability that are essential to a better understanding of real environmental problems, including social, economic and physical aspects. Thus, this article presents the use of a Multi-agent System for Environmental Simulation (MASE) for exploring potential impacts of land use policies. MASE is a freeware multi-agent model system to simulate LUCC dynamics that is illustrated with the Brazilian Cerrado case. Considering the experimental results, we consider that MASE represents an interesting alternative for LUCC decision support.
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- 2014
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171. Description of development, light interception and growth of sunflower at two sowing dates and two densities
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F. G. Abreu and A. M. Ferreira
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Canopy ,Numerical Analysis ,General Computer Science ,Phenology ,Applied Mathematics ,Sowing ,Sunflower ,Theoretical Computer Science ,Crop ,Agronomy ,Modeling and Simulation ,Environmental science ,Dry matter ,Interception ,Leaf area index - Abstract
The relationship between dry matter production and solar radiation interception by plant canopies is well known for several crops including sunflower. The effects of temperature environment on sunflower development have also been subject of much research. However, under seasonal rainfall, management strategies, such as the choice of sowing dates and of plant densities may change crop responses to temperature and radiation, preventing the use of standard relationships. The object of this work is to study the influence of two sowing dates on crop development and two plant densities on light interception and growth of sunflower crops grown on stored soil water in the semi-arid Mediterranean region of southern Portugal. The cultivar “Florassol” was sown at Evora, Portugal on 13 March 1997 (S1) and on 5 May 1997 (S2) and in each sowing date at the densities of 11.4 plants m−2 (D1) and 4 plants m−2 (D2). Leaf number, leaf area and above-ground dry matter were measured weekly throughout the crop cycle. Meteorological parameters and canopy light transmission were measured continuously. Crop development was slower in S1 than in S2 because of cooler temperatures during crop cycle in S1 but thermal requirements for each development phase were similar. Temperature, though affecting the duration of phenological phases, did not affect maximum leaf area per plant, which was similar for the same plant density in both sowing dates. For the first sowing, significant differences in dry matter production and light interception were found between the two densities. Crop dry matter production and solar radiation interception were smaller in D2 than in D1 owing to a greater leaf area index in D1, although leaf area and above-ground dry mass per plant were higher in the lower density (D2). Leaf number, canopy light extinction coefficient and the radiation use efficiency were similar in both densities.
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- 2001
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172. Texture in Cold Rolled and Magnetically Aged Fe–Mo–Ni–C Alloys
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J. R. Teodósio, C. S. Da Costa Viana, and H. F. G. Abreu
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Shear (sheet metal) ,Magnetic anisotropy ,Materials science ,Distribution function ,chemistry ,Metallurgy ,chemistry.chemical_element ,Texture (crystalline) ,Carbon - Abstract
The texture change due to the increase of cold rolling reduction in Fe-Mo-Ni-C alloys is described. Orientation Distribution Functions (ODF) for samples cold rolled 80%, 90%, 97% and 99% are shown and discussed. Below 90% cold rolling reduction, the texture in these alloys is similar to that of cold rolled low carbon steels. Above 90% cold rolling reduction, a decrease in the component {001}〈110〉 is observed and the texture becomes weaker probably due to the development of shear bands. Magnetic age-annealing at 610°C for 1 h does not recrystallize completely these alloys. Samples cold rolled above 90% (97% and 99%) present an increase in the {001}〈110〉 component, this being responsible for a corresponding increase in the magnetic anisotropy of these alloys.
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- 1998
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173. Sterol carrier protein 2 regulates proximal tubule size in the Xenopus pronephric kidney by modulating lipid rafts
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José G. Abreu, Oliver Wessely, Daniel Romaker, Débora M. Cerqueira, and Uyen Tran
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Transcription, Genetic ,Xenopus ,Organ size control ,Xenopus Proteins ,Pronephros ,Article ,Sterol carrier protein 2 ,Cell Line ,Morpholinos ,Kidney Tubules, Proximal ,Xenopus laevis ,Membrane Microdomains ,medicine ,Animals ,Humans ,Lovastatin ,RNA, Messenger ,Molecular Biology ,Lipid raft ,Lipid rafts ,SCP2 ,Body Patterning ,Kidney ,biology ,Anticholesteremic Agents ,HEK 293 cells ,Cell Biology ,biology.organism_classification ,Cell biology ,medicine.anatomical_structure ,Sterol carrier protein ,Cholesterol ,HEK293 Cells ,Gene Knockdown Techniques ,lipids (amino acids, peptides, and proteins) ,Signal transduction ,Carrier Proteins ,Developmental Biology - Abstract
The kidney is a homeostatic organ required for waste excretion and reabsorption of water, salts and other macromolecules. To this end, a complex series of developmental steps ensures the formation of a correctly patterned and properly proportioned organ. While previous studies have mainly focused on the individual signaling pathways, the formation of higher order receptor complexes in lipid rafts is an equally important aspect. These membrane platforms are characterized by differences in local lipid and protein compositions. Indeed, the cells in the Xenopus pronephric kidney were positive for the lipid raft markers ganglioside GM1 and Caveolin-1. To specifically interfere with lipid raft function in vivo, we focused on the Sterol Carrier Protein 2 (scp2), a multifunctional protein that is an important player in remodeling lipid raft composition. In Xenopus, scp2 mRNA was strongly expressed in differentiated epithelial structures of the pronephric kidney. Knockdown of scp2 did not interfere with the patterning of the kidney along its proximo-distal axis, but dramatically decreased the size of the kidney, in particular the proximal tubules. This phenotype was accompanied by a reduction of lipid rafts, but was independent of the peroxisomal or transcriptional activities of scp2. Finally, disrupting lipid micro-domains by inhibiting cholesterol synthesis using Mevinolin phenocopied the defects seen in scp2 morphants. Together these data underscore the importance for localized signaling platforms in the proper formation of the Xenopus kidney.
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- 2013
174. Phenotypic detection of metallo-β-lactamases in Pseudomonas aeruginosa and Acinetobacter baumannii isolated from hospitalized patients in São Luis, State of Maranhão, Brazil
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Silvio Gomes Monteiro, Azizedite Guedes Gonçalves, Sirlei Garcia Marques, Afonso G. Abreu, Luís Henrique Bastos Gonçalves, and Roberto Morais Luz de Carvalho
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Microbiology (medical) ,Acinetobacter baumannii ,lcsh:Arctic medicine. Tropical medicine ,Hospitalized patients ,lcsh:RC955-962 ,medicine.disease_cause ,Metallo β lactamase ,beta-Lactam Resistance ,beta-Lactamases ,Microbiology ,Disk Diffusion Antimicrobial Tests ,medicine ,Humans ,Metallo--lactamases ,biology ,Pseudomonas aeruginosa ,Outbreak ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,bacterial infections and mycoses ,Anti-Bacterial Agents ,Infectious Diseases ,Phenotype ,Parasitology - Abstract
Introduction Acquired metallo-β-lactamases (MβL) are emerging determinants of resistance in Pseudomonas aeruginosa and Acinetobacter baumannii. The objectives of this study were to phenotypically detect MβL in imipenem-resistant P. aeruginosa and A. baumannii, to investigate the association between MβL-positive strains and hospitals, and to compare the resistance profiles of MβL-producing and non-MβL-producing strains. Methods The approximation disk and combined disk assay methods were used in this study. Results A total of 18 (38.3%) P. aeruginosa isolates and 1 (5.6%) A. baumannii isolate tested positive for the presence of MβL. Conclusions These results demonstrate the need for strict surveillance and for the adoption of preventive measures to reduce the spread of infection and potential outbreaks of disease caused by MβL-producing microorganisms.
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- 2013
175. Development and Characterization of Microsatellite Markers for the Medicinal Plant Smilax brasiliensis (Smilacaceae) and Related Species
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Aline Redondo Martins, Miklos Maximiliano Bajay, Beatriz Appezzato-da-Glória, Mariza Monteiro, Carlos Eduardo de Araújo Batista, Glyn Mara Figueira, Alessandro Alves-Pereira, Aluana G. Abreu, José Baldin Pinheiro, Priscilla Marqui Schmidt Villela, and Maria Imaculada Zucchi
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Genetic diversity ,Traditional medicine ,biology ,transferability ,Smilax ,Plant Science ,biology.organism_classification ,Primer Note ,microsatellites ,Gene flow ,lcsh:QK1-989 ,medicinal plant ,sarsaparilla ,lcsh:Biology (General) ,lcsh:Botany ,Botany ,Microsatellite ,Sarsaparilla ,Genomic library ,Smilacaceae ,Allele ,lcsh:QH301-705.5 ,Ecology, Evolution, Behavior and Systematics - Abstract
Premise of the study: A new set of microsatellite or simple sequence repeat (SSR) markers were developed for Smilax brasiliensis, which is popularly known as sarsaparilla and used in folk medicine as a tonic, antirheumatic, and antisyphilitic. Smilax brasiliensis is sold in Brazilian pharmacies, and its origin and effectiveness are not subject to quality control. Methods and Results: Using a protocol for genomic library enrichment, primer pairs were developed for 26 microsatellite loci and validated in 17 accessions of S. brasiliensis. Thirteen loci were polymorphic and four were monomorphic. The primers successfully amplified alleles in the congeners S. campestris, S. cissoides, S. fluminensis, S . goyazana, S. polyantha, S. quinquenervia, S. rufescens, S. subsessiliflora, and S. syphilitica. Conclusions: The new SSR markers described herein are informative tools for genetic diversity and gene flow studies in S. brasiliensis and several congeners.
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- 2013
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176. Wnt stabilization of β-catenin reveals principles for morphogen receptor-scaffold assemblies
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José G. Abreu, Mikhail V. Semonov, Xi He, He Huang, Ming Zhao, Aili Zhang, Bryan T. MacDonald, Leilei Peng, Sung Eun Kim, Xinjun Zhang, and Xiaowu Zhang
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Xenopus ,Molecular Sequence Data ,macromolecular substances ,Biology ,Article ,Dephosphorylation ,Glycogen Synthase Kinase 3 ,Axin Protein ,Animals ,Humans ,Amino Acid Sequence ,Phosphorylation ,beta Catenin ,Multidisciplinary ,Protein Stability ,Wnt signaling pathway ,LRP6 ,biology.organism_classification ,Cell biology ,Wnt Proteins ,HEK293 Cells ,Catenin ,Low Density Lipoprotein Receptor-Related Protein-6 ,Signal transduction ,Morphogen ,HeLa Cells ,Signal Transduction - Abstract
Signal Scaffolds Scaffolds in cellular signaling pathways are turning out to do way more than just hold proteins together in a complex. Kim et al. (p. 867 , published online 11 April) showed the importance of the scaffold protein Axin as an active participant controlling the kinetics of activation of signaling through the pathways. Axin is part of two protein complexes that have opposing actions that may regulate the timing of signaling—either activating Wnt signaling, thus protecting β-catenin from destruction, or causing proteolytic destruction of β-catenin. Rock et al. (p. 871 , published online 11 April) characterized the role of the scaffold protein Nud1 in the mitotic exit network and found that the kinase that produces the output from the signaling complex only interacts with a scaffold that is primed by its activator protein kinase, already bound to the scaffold and creating a docking site.
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- 2013
177. Genetic structure and gene flow among Brazilian populations of Heliothis virescens (Lepidoptera: Noctuidae)
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Felipe A, Domingues, Karina L, Silva-Brandão, Aluana G, Abreu, Omaththage P, Perera, Carlos A, Blanco, Fernando L, Cônsoli, and Celso, Omoto
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Gene Flow ,Gossypium ,Animals ,Genetic Variation ,Soybeans ,Moths ,Brazil ,Microsatellite Repeats - Abstract
Population genetic studies are essential to the better application of pest management strategies, including the monitoring of the evolution of resistance to insecticides and genetically modified plants. Bacillus thuringiensis Berliner (Bt) crops have been instrumental in controlling tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), a pest that has developed resistance to many common insecticides once used for its management. In our study, microsatellite markers were applied to investigate the genetic structure and patterns of gene flow among Brazilian populations of H. virescens from cotton, Gossypium hirsutum L., and soybean, Glycine max (L.) Merr., fields, aiming to propose means to improve its management in the field. In total, 127 alleles were found across nine microsatellites loci for 205 individuals from 12 localities. Low levels of gene flow and moderate to great genetic structure were found for these populations. Host plant association, crop growing season, and geographic origin were not responsible for the genetic structuring among Brazilian populations of H. virescens. Other factors, such as demographic history and seasonal variability of intrapopulation genetic variation, were suggested to be molding the current pattern of genetic variability distribution.
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- 2013
178. Entity Extraction within Plain-Text Collections WISE 2013 Challenge - T1: Entity Linking Track
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Lucas Borges Monteiro, Patrícia Lustosa, Luiz Fernando Peres de Oliveira, Carolina G. Abreu, Flávio Murilo Pereira da Costa, Laécio L. Santos, and Li Weigang
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Entity linking ,Identification (information) ,Information extraction ,Information retrieval ,Text processing ,Computer science ,Plain text ,Proper noun ,computer.file_format ,computer.software_genre ,Pipeline (software) ,computer ,Domain (software engineering) - Abstract
The WISE 2013 conference proposed a challenge (T1 Track) in which teams must label entities within plain texts based on Wikilinks dataset which comprises 40 million mentions over 3 million existed entities. This paper describe a straightforward two-fold unsupervised strategy to extract and tag entities, aiming to achieve accurate results in the identification of proper nouns and concrete concepts, regardless the domain. The proposed solution is based on a pipeline of text processing modules that includes a lexical parser. The solution labelled 8824 texts, and the results achieved satisfying precision measures.
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- 2013
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179. Comportamento ingestivo de novilhas suplementadas a pasto sob nutrição compensatória
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G.G.P. Carvalho, H. A. Santana Júnior, F. B. L. Mendes, G. Trindade Júnior, G. Abreu Filho, R. R. Silva, Daniele Soares Barroso, Daniel Lucas Santos Dias, A. A. Pinheiro, E. O. Cardoso, and Fabiano Ferreira da Silva
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Bovino ,Etologia ,Animal science ,Animal Science and Zoology ,Pastejo ,Biology ,Consumo ,Ruminante - Abstract
EnglishThe study was conducted to evaluate the effects of compensatory nutrition on supplemented pasture heifers on ingestive behavior. The experiment was conducted on the farm Princesa do Mateiro, Ribeirao do Largo, Bahia. Twenty 5/8 Guzera Dairy 3/8 Hostein heifers, with an average of 18 months of age and body weight of 187 ± 13.07 kg were used. The experiment lasted 224 days and the animals were maintained in pasture production, rotational grazing Brachiaria brizantha 'Marandu'. The animals were randomly assigned to each of the treatments: control (T100): Animals fed concentrate to supply 100 % of the requirement of nutrients to gain 750 g/day; compensatory nutrition (CN): animals that alternated the feed level periodically being restricted fed concentrate to meet the requirement of 80 % total digestible nutrients of the control treatment (T80) and refeeding fed concentrate to supply 120 % of the total digestible nutrient requirements of the control treatment (T120). In periods of restriction, the average grazing time was greater for NC (533 vs. 426 minutes) (p0.05). During refeeding, the number of bits by swallowing, swallowing time and number of bites per day were lower (p portuguesO estudo foi realizado com o objetivo de avaliar os efeitos da nutricao compensatoria em novilhas suplementadas a pasto sobre o comportamento ingestivo. O experimento foi conduzido na fazenda Princesa do Mateiro, municipio de Ribeirao do Largo, Bahia. Foram utilizadas 20 novilhas com grau de sangue 5/8 Guzera Leiteiro 3/8 Holandes, com media de 18 meses de idade e peso corporal medio de 187 ± 13,07 kg. O experimento teve duracao de 224 dias e os animais foram mantidos em sistema de producao a pasto, em pastejo rotacionado de Brachiaria brizantha 'Marandu'. Os animais foram aleatoriamente alocados em cada um dos tratamentos: Controle (T100): Animais recebendo concentrado para suprir 100 % da exigencia de nutrientes para ganho de 750 g/dia; Nutricao compensatoria (NC): Animais que alternaram o nivel de alimentacao entre os perio- dos, sendo que nos periodos de restricao receberam concentrado para suprir 80 % da exigencia de nutrientes digestiveis totais do tratamento controle (T80) e nos periodos de realimentacao receberam concentrado para suprir 120 % das exigencias de nutrientes digestiveis totais do tratamento controle (T120). Nos periodos de restricao, as medias do tempo de pastejo foram maiores para o NC (533 vs. 426 minutos) (p Os tempos de pastejo e ruminacao, nos periodos de realimentacao foram inferiores nos animais do grupo NC (p No periodo de restricao, nao houve diferencas estatisticas entre o controle e a nutricao compensatoria para nenhuma das variaveis dos bocados e degluticao (p>0,05). No periodo de realimentacao, o numero de bocados por degluticao tempo por degluticao, numeros de bo- cados por dia, os valores foram inferiores (p
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- 2013
180. There is still time to treat?
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G. Abreu, AP Pacheco, C. Viana, S Esperança, N. Fernandes, and F. Gonçalves
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medicine.medical_specialty ,business.industry ,Hidratação ,Internal Medicine ,medicine ,Choque ,Intensive care medicine ,business - Published
- 2013
181. Autotransporter Protein-Encoding Genes of Diarrheagenic Escherichia coli Are Found in both Typical and Atypical Enteropathogenic E. coli Strains
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Fernando Navarro-Garcia, Waldir P. Elias, Afonso G. Abreu, Vanessa Bueris, Tatiane M. Porangaba, and Marcelo Palma Sircili
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Virulence Factors ,Virulence ,Genetics and Molecular Biology ,Biology ,Applied Microbiology and Biotechnology ,Microbiology ,Enteropathogenic Escherichia coli ,parasitic diseases ,Gene ,Enteropathogenic E. coli ,Escherichia coli Infections ,Molecular Epidemiology ,Ecology ,Molecular epidemiology ,Diarrheagenic Escherichia coli ,Membrane transport protein ,Escherichia coli Proteins ,Membrane Transport Proteins ,biochemical phenomena, metabolism, and nutrition ,biology.protein ,Autotransporter domain ,bacteria ,population characteristics ,Food Science ,Biotechnology - Abstract
Autotransporter (AT) protein-encoding genes of diarrheagenic Escherichia coli (DEC) pathotypes ( cah , eatA , ehaABCDJ , espC , espI , espP , pet , pic , sat , and tibA ) were detected in typical and atypical enteropathogenic E. coli (EPEC) in frequencies between 0.8% and 39.3%. Although these ATs have been described in particular DEC pathotypes, their presence in EPEC indicates that they should not be considered specific virulence markers.
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- 2013
182. Protein glycation and in vivo distribution of human lens fluorescence
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G. Abreu, Evorah Lusci Costa Cardoso, M. C. Mota, José S. Ramalho, P. Carvalho, and A. M. Gaspar
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Adult ,Aging ,Glycosylation ,High-performance liquid chromatography ,Cataract ,Fluorescence ,Fluorophotometry ,Fluorescence spectroscopy ,Lens protein ,symbols.namesake ,Cataracts ,Glycation ,In vivo ,Lens, Crystalline ,Photography ,medicine ,Humans ,Chromatography, High Pressure Liquid ,Aged ,Aged, 80 and over ,business.industry ,Lysine ,Middle Aged ,medicine.disease ,Crystallins ,In vitro ,Maillard Reaction ,Ophthalmology ,Maillard reaction ,Diabetes Mellitus, Type 1 ,Glucose ,Biochemistry ,symbols ,business - Abstract
Glycated proteins formed by the Maillard reaction were measured by furosine determination in human normal lenses and in senile and diabetic cataracts. Furosine, an hydrolysis product of fructose-lysine adduct formed in the early stages of the Maillard reaction, was measured by high performance liquid chromatography (HPLC). Furosine levels in diabetic cataracts were found to be 3 to 4 times higher than those observed for senile cataracts. The increased glycation levels both in cortex and nucleus were related to the increase of fluorescence determined in vitro by fluorometry and in vivo by Scheimpflug photography. Lens proteins were incubated with glucose and it has been demonstrated that protein glycation occurred parallel with the increase in concentration of fluorescent chromophores that present similar characteristics as those observed in vivo. The results indicate that protein insolubilization seemed to involve preferentially glycated proteins and at least in diabetic cataracts, the process seems to be initiated in the cortical region.
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- 1995
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183. Early growth of invasive acacias as a potential biomass-for-energy source under Mediterranean conditions
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Rita Moreira, António Fabião, Francisco G. Abreu, Marta Carneiro, and Jorge Gominho
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Mediterranean climate ,Biomass (ecology) ,Ecology ,biology ,Acacia dealbata ,Acacia pycnantha ,Agroforestry ,05 social sciences ,Acacia ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,biology.organism_classification ,01 natural sciences ,Agronomy ,Eucalyptus globulus ,050501 criminology ,Acacia melanoxylon ,Energy source ,Agronomy and Crop Science ,0505 law ,0105 earth and related environmental sciences - Abstract
Most of the short rotation energy coppices used in Northern and Central Europe may be of limited value under Mediterranean climates. Abandoned acacia stands with an invasive behaviour, of environmental concern in many Mediterranean countries, may perform better as biomass producers under summer drought than those coppices. Seedlings of invasive Acacia dealbata, A. melanoxylon and A. pycnantha were planted to test for early growth performance under rain-fed and irrigated conditions. Rooted cuttings of an E. globulus clone were also established as a reference for biomass production. Plants were harvested after one year, sorted by biomass components and oven-dried. Above-ground dry weight was calculated on an area basis, accounting for survival. A. dealbata and A. melanoxylon showed low survival and biomass production, even irrigated, whereas A. pycnantha had better survival and growth performance than eucalypt, even in rain-fed plots, suggesting potential for the harvest of this drought-adapted species as a biomass source.
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- 2016
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184. Effects of natural compounds on Xenopus embryogenesis: a potential read out for functional drug discovery targeting Wnt/β-catenin signaling
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Fabio A. Mendes, José G. Abreu, Débora M. Cerqueira, Alice H. Reis, Barbara F. Fonseca, Nathalia G. Amado, Ricardo Machado Kuster, and Alessandro Bolis Costa Simas
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Biological Products ,Base Sequence ,Drug discovery ,Reverse Transcriptase Polymerase Chain Reaction ,Xenopus ,Wnt signaling pathway ,LRP6 ,Embryonic Development ,LRP5 ,General Medicine ,Biology ,biology.organism_classification ,Phenotype ,Cell biology ,Wnt Proteins ,In vivo ,Drug Discovery ,Animals ,Signal transduction ,beta Catenin ,DNA Primers ,Signal Transduction - Abstract
Maternal Wnt/β-Catenin signaling is essential to establish dorsal-specific gene expression required for axial patterning in Xenopus. Deregulation of this pathway causes axis phenotypes in frog embryos. In adult life, mutations in the Wnt pathway components are associated with many diseases, such as polyposis coli; osteoporosis-pseudoglioma syndrome (OPPG); skeletal dysplasia; neural tube defects, cancer and many others. Thus, a better understanding of Wnt/β-catenin signaling will have great and significant impact on Biology and Medicine. In this aspect, natural compounds are potential targets as novel molecules that could modulate the Wnt pathway. For instance, flavonoids are a large group of natural compounds found in plants that modulate important cellular and molecular mechanisms related to diseases, but the specific in vivo mechanism of action of most flavonoids remain unknown. In this way, Xenopus embryos may provide an efficient model, since it is frequently used to test and identify the role of molecules that affect Wnt/β-catenin signaling. Here, we describe a combination of approaches to outline and characterize the role of two flavonoids, quercetin and rutin, on Wnt/β-catenin signaling, using Xenopus embryos as an experimental model. Our data support that quercetin is potential in vivo modulator of canonical Wnt signaling and that this effect might depend on the structure of this molecule, as we did not observe any effect with rutin treatment, a flavonol structurally-related to quercetin. This model is useful to analyze effects of quercetin and other flavonoids in vivo and to provide further understanding of how natural compounds can modulate signaling pathways, using Xenopus embryos as a fast and efficient reading of in vivo effects of those compounds.
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- 2012
185. Saliva and blood interferon gamma levels and IFNG genotypes in acute graft-versus-host disease
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R G, Resende, J D F, Correia-Silva, T A, Silva, S G, Xavier, H, Bittencourt, R S, Gomez, and M H N G, Abreu
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Adult ,Male ,Transplantation Conditioning ,Adolescent ,Genotype ,Graft vs Host Disease ,Interferon-gamma ,Young Adult ,Humans ,Transplantation, Homologous ,Prospective Studies ,Salivary Proteins and Peptides ,Child ,Saliva ,Aged ,Polymorphism, Genetic ,Adenine ,Hematopoietic Stem Cell Transplantation ,Middle Aged ,Tissue Donors ,Treatment Outcome ,Child, Preschool ,Acute Disease ,Female ,Biomarkers ,Thymine ,Follow-Up Studies ,Forecasting - Abstract
Graft-versus-host disease is a major complication after allogenic hematopoietic stem cell transplantation. Interferon gamma is an important pro-inflammatory cytokine involved in this disease. Cytokine gene polymorphisms are associated with functional differences in cytokine expression and can alter the clinical course of graft-versus-host disease. This study aimed to investigate the association between IFN-γ levels in saliva, blood, and IFNG polymorphisms, as well as the occurrence of acute graft-versus-host disease in allogenic HSCT.Fifty-eight consecutive allogenic hematopoietic stem cell transplantation recipients and their donors were prospectively studied. IFN-g levels in saliva and blood were assessed by ELISA. Samples were collected weekly from 7 days before transplantation (day -7) to 100 days after allogenic HSCT (day +100) or until death. Saliva and/or blood samples were obtained from the recipients and donors to determine IFNG gene polymorphisms. Increased saliva and blood IFN-g levels were observed in patients that had developed aGVHD. In the saliva, the peak levels of IFN-g could be found one week before aGVHD diagnosis, while in the blood, peak levels of IFN-g could be only observed upon diagnosis. A significant association could be identified between the recipients'IFNG genotypes and the IFN-g levels in their blood, at +14 days after HSCT. No association could be observed between IFNG gene polymorphisms and the aGVHD. The present study shows that the genetic background of recipients can influence the production of IFN-g. Moreover, as IFN-g levels in the saliva and blood were found to be associated with aGVHD development, this cytokine may be a useful predictor of acute graft-versus-host disease.
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- 2012
186. MtDNA variability in whitefly (Bemisia tabaci) populations in Brazil
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Giuliana Etore do Valle, José Baldin Pinheiro, Maria Imaculada Zucchi, André Luiz Lourenção, and Aluana G. Abreu
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Gene Flow ,Genetic Markers ,Population ,Zoology ,Genes, Insect ,Whitefly ,DNA, Mitochondrial ,Hemiptera ,Plant virus ,Genetics ,Animals ,Genetic variability ,education ,Molecular Biology ,Phylogeny ,education.field_of_study ,biology ,Base Sequence ,Genetic Variation ,General Medicine ,Sequence Analysis, DNA ,biology.organism_classification ,GenBank ,Genetic structure ,PEST analysis ,Brazil - Abstract
Bemisia tabaci (Hemiptera: Aleyrodidae) consists of a complex of morphologically indistinct biotypes that vary mainly in their capacity to transmit plant viruses and to induce physiological disorders in plants of economic importance. The adaptability of B. tabaci to many regions of the world has fostered the appearance of various biotypes and has resulted in a broad spectrum of host plants. Our goal was to identify which biotypes were present in four B. tabaci populations in Brazil. We quantified genetic variability between and within populations. Three individuals were collected from three host plant species: two populations on soybean (Campinas and Rondonopolis), one on pumpkin (Barreiras) and one on tomato (Cruz das Almas) in three States of Brazil (Sao Paulo, Mato Grosso, and Bahia). We chose one sequence of the B biotype, obtained from GenBank; the Campinas population, which had been previously characterized as biotype B, was used as a control for this biotype. We also included one sequence of the Q biotype, obtained from GenBank, as an outgroup. The COI region of the mtDNA gene was partially amplified with the CI-J-2195 and L2-N-3014 pair of primers, and the reaction products were sequenced. Based on distance-based algorithm analyses, we found that all haplotypes belong to biotype B, which was confirmed by the haplotype network. Genetic structure analyses showed that the host plant species does not influence population structuring of this pest; only the geographic location mattered.
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- 2011
187. Ferramenta de Simulação com Abordagem de Sistema Multiagente Híbrida para Gestão Ambiental
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Alexandre Zaghetto, Bruno Macchiavello, Carolina G. Abreu, Célia Ghedini Ralha, and Cassio G. C. Coelho
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O presente artigo introduz um protótipo para um sistema computacional que possibilita a realização de simulações do uso do solo. O sistema proposto e uma evolução de um trabalho anterior e tem como objetivo auxiliar na análise da dinâmica do uso e cobertura do solo, de tal forma que possa servir como uma ferramenta utilizada na tomada de decisões. O sistema utiliza uma abordagem multiagentes e modelo configurável pelo usuário. O modelo leva em consideração certas variáveis proximais como por exemplo a presença de estradas, edificações, cursos de água, etc. Estas variáveis proximais são utilizadas para identificar as regiões com maior probabilidade de uso antrópico. O sistema apresenta o potencial para que o usuário seja capaz de configurar o modelo de simulação indicando quais variáveis de proximais serão levadas em consideração, a importância de cada uma delas e inclusive a máquina de estados a ser utilizada durante a simulação. O sistema multiagentes permite a elaboração de diversos comportamentos dos agentes envolvidos podendo gerar diferentes cenários de simulação. São também apresentadas simulações iniciais para o bioma do cerrado. O cerrado e um dos maiores biomas brasileiros e considerado um hotspot da biodiversidade
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- 2011
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188. Three dimensional modeling applied to breast cancer
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A. P. B. Silva, C. G. Abreu, J. M. Lamas, Lourdes Mattos Brasil, M. G. Barros, and M. R. Parente
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business.industry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Dimensional modeling ,Solid modeling ,Virtual reality ,3D modeling ,Machine learning ,computer.software_genre ,medicine.disease ,Object (computer science) ,ComputingMethodologies_PATTERNRECOGNITION ,Software ,Breast cancer ,Medicine ,Virtual training ,Artificial intelligence ,skin and connective tissue diseases ,business ,computer ,Simulation - Abstract
This paper presents three-dimensional modeling as a tool for education in health, being the object for integration with Virtual Reality and Artificial Intelligence. The choose for the application area was the anatomical structure of the breast, especially for the importance of a clinical model for virtual training aid in the detection of breast cancer.
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- 2011
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189. HCMV gB genotype and its association with cytokine levels in hematopoietic stem cell transplantation
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J F, Correia-Silva, R G, Resende, T C, Arão, M H N G, Abreu, M M, Teixeira, H, Bittencourt, T A, Silva, and R S, Gomez
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Adult ,Male ,Transplantation Conditioning ,Adolescent ,Genotype ,Interleukin-1beta ,Cytomegalovirus ,Opportunistic Infections ,Immunocompromised Host ,Interferon-gamma ,Young Adult ,Viral Envelope Proteins ,Humans ,Transplantation, Homologous ,Child ,Saliva ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Hematopoietic Stem Cell Transplantation ,Middle Aged ,Interleukin-10 ,Survival Rate ,Child, Preschool ,Cytomegalovirus Infections ,Cytokines ,Female ,Follow-Up Studies - Abstract
Glycoprotein B (gB) has been implicated in determining the pathogenicity and clinical outcomes of human cytomegalovirus (HCMV) disease.The purpose of this study was to assess the prevalence of gB genotypes in allogeneic hematopoietic stem cell transplantation (allo-HSCT) and the relationship between it and cytokine levels in saliva and blood samples. The impact of these parameters on patients' survival was also investigated.Samples were obtained from 63 patients receiving an allo-HSCT. HCMV gB genotyping was carried out by multiplex nested PCR. The cytokine levels were assessed using ELISA assay.A single or mixed genotype infection was detected in the saliva and blood of 36/63 and 52/63 subjects, respectively. Patients with gB2 in their saliva showed lower IL-10 levels in comparison with patients without gB2. Reduced blood levels of IFN-γ and IL-1β were also found in recipients with the HCMV gB4 genotype compared with patients without it. Decreased IL-1β and increased IL-10 blood levels were associated with lower survival. However, HCMV gB genotypes have no impact on patient outcome.Decreased IL-1β and increased IL-10 levels in the blood are associated with lower survival. HCMV genotypes are associated with different cytokine levels in saliva and blood.
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- 2011
190. Nosocomial infection and characterization of extended-spectrum β-lactamases-producing Enterobacteriaceae in Northeast Brazil
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Sirlei Garcia Marques, Afonso G. Abreu, Valério Monteiro-Neto, Roberto Morais Luz de Carvalho, and Azizedite Guedes Gonçalves
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Microbiology (medical) ,lcsh:Arctic medicine. Tropical medicine ,lcsh:RC955-962 ,medicine.drug_class ,Klebsiella pneumoniae ,Antibiotics ,Infecção hospitalar ,Microbial Sensitivity Tests ,medicine.disease_cause ,Antimicrobial resistance ,beta-Lactam Resistance ,beta-Lactamases ,Microbiology ,Antibiotic resistance ,Nosocomial infection ,Enterobacteriaceae ,Clavulanic acid ,medicine ,polycyclic compounds ,Humans ,Escherichia coli ,Cross Infection ,biology ,Enterobacteriaceae Infections ,Klebsiella oxytoca ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,bacterial infections and mycoses ,Proteus mirabilis ,Enterobactérias ,Anti-Bacterial Agents ,Infectious Diseases ,Phenotype ,ESBLs ,bacteria ,Parasitology ,Resistência antimicrobiana ,Brazil ,medicine.drug - Abstract
INTRODUCTION: Extended spectrum β-lactamases (ESBLs) are enzymes that degrade β-lactam antibiotics and have been reported to be an important cause of nosocomial infection in worldwide. METHODS: During 2009, 659 enterobacteria strains were isolated from different clinical specimens and tested for ESBL production. The disk approximation test, combined disk method and addition of clavulanic acid were used for phenotypic detection of the ESBL-producing strains and PCR for detection of the blaTEM and blaCTX-M genes. RESULTS: Among the isolates, 125 were ESBL producers. The blaCTX-M and blaTEM genes were detected in 90.4% and 75% of the strains, respectively. Most strains were isolated from urine. Klebsiella pneumoniae was the most prevalent organism. Microorganisms presented high resistance to the antibiotics. CONCLUSIONS: These results support the need for extending ESBL detection methods to different pathogens of the Enterobacteriaceae family because these methods are only currently standardized by the CLSI for Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Proteus mirabilis. Carbapenems were the antibiotic class of choice for the treatment of infections caused by ESBL-producing Enterobacteriaceae.
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- 2011
191. EVOLUTION OF RECRYSTALLIZATION BY CHANGES IN MAGNETIC HYSTERESIS LOOP IN A NON-ORIENTED ELECTRIC STEEL COLD ROLLED
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F. E. da Silva, F. N. C. Freitas, H. F. G. Abreu, L. L. Gonçalves, E. P. Moura, M. R. Silva, Donald O. Thompson, and Dale E. Chimenti
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Electric motor ,Electric steel ,Fabrication ,Materials science ,Annealing (metallurgy) ,business.industry ,Magnetometer ,Structural engineering ,Coercivity ,Magnetic hysteresis ,Recrystallization (chemistry) ,law.invention ,law ,Composite material ,business - Abstract
Non‐oriented steels, with low carbon, are widely used in the fabrication of electrical motor nucleus. The performance of these motors is affected by the level of recrystallization. These steels can come from the steel plant in two different conditions: totally processed or semi‐processed. The semi‐processed steels have a partially deformed structure and are submitted to the final annealing process after reaching the end shape. An adequate annealing heat treatment is important to get an appropriate magnetic property. In the present study, samples of an electric steel, with the composition (0.05 wt% C, 1.28wt% Si, 0.29wt% Mn), cold rolled 50% in thickness, were withdrawn during the industrial heat treatment at temperatures of 575, 580, 600, 620 and 730 °C with the objective of evaluating the evolution of recrystalization with temperature. Magnetic properties were measured at room temperature in a vibrating sample magnetometer. Although the changes in magnetic hysteresis loop with temperature are difficult t...
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- 2011
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192. Case-based session Club 35: Friday 5 December 2014, 10:00-11:00 * Location: Agora
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Y. De Greef, Y.-J. Choi, L. Riahi, K. Yamagata, P. Van Den Heuvel, C.-H. Lee, K.-H. Park, Matteo Cameli, Carlos Galvão Braga, Dirk Stockman, H. Felice, Catarina Vieira, P. Dingli, Sergio Mondillo, U. Kim, L. Reichmuth, J.-W. Son, S. Casini, R. Prisecaru, H.-J. Kim, D.-G. Shin, Stefano Lunghetti, Sérgio Nabais, J. A. Salerno-Uriarte, Y.-J. Kim, Carina Arantes, Paola Azevedo, A. J. Salgado, M. Pappalettera, J Martins, Carlo Pierli, A. Geyer, G Abreu, S.-H. Lee, F. Zuffada, Flavio D'Ascenzi, M. Bolatti, Adelino Correia, J.-S. Park, Bruno Schwagten, Massimo Fineschi, and F. Airoldi
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business.industry ,Library science ,Medicine ,Radiology, Nuclear Medicine and imaging ,Agora ,General Medicine ,Club ,Session (computer science) ,Cardiology and Cardiovascular Medicine ,business ,computer ,computer.programming_language - Published
- 2014
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193. Flavonoids: potential Wnt/beta-catenin signaling modulators in cancer
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Vivaldo Moura Neto, Barbara F. Fonseca, Nathalia G. Amado, Débora M. Cerqueira, and José G. Abreu
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Cell signaling ,Natural compounds ,Biology ,Inhibitory postsynaptic potential ,General Biochemistry, Genetics and Molecular Biology ,Wnt signaling pathway ,Pharmacology, Toxicology and Pharmaceutics(all) ,Neoplasms ,medicine ,Isoquercitrin ,Animals ,Humans ,General Pharmacology, Toxicology and Pharmaceutics ,Mode of action ,Autocrine signalling ,Tissue homeostasis ,beta Catenin ,Cancer ,Flavonoids ,Biochemistry, Genetics and Molecular Biology(all) ,Small molecules ,fungi ,Polyphenols ,food and beverages ,General Medicine ,Plants ,medicine.disease ,Cell biology ,Wnt Proteins ,Signal transduction ,Signal Transduction - Abstract
Flavonoids are polyphenolic compounds found throughout the plant kingdom. They occur in every organ but are usually concentrated in leaves and flowers. During the last two decades, in vitro and in vivo studies demonstrated that flavonoids have inhibitory effects on human diseases through targeting of multiple cellular signaling components. Wnt/β-catenin signaling regulates proliferation, differentiation and fate specification in developmental stages and controls tissue homeostasis in adult life. For these reasons, this pathway has received great attention in the last years as potential pathway involved in distinct Human pathologies. In this review we discuss the emerging potential mechanisms for flavonoids on Wnt/β-catenin signaling in cancer and possible investigation strategies to understand flavonoids mode of action on this signaling pathway.
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- 2010
194. Effect of pacing-induced ventricular dyssynchrony on right ventricular function
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Maria Carmo P, Nunes, Cláudia Drumond G, Abreu, Antônio Luiz P, Ribeiro, Marcia M, Barbosa, Leonor G, Rincon, Rodrigo Citton P, Reis, and Manoel Otávio C, Rocha
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Adult ,Heart Failure ,Male ,Ventricular Dysfunction, Left ,Ventricular Dysfunction, Right ,Cardiac Pacing, Artificial ,Humans ,Female ,Treatment Failure ,Middle Aged - Abstract
Asynchronous electrical activation induced by right ventricular (RV) pacing can cause several abnormalities in left ventricular (LV) function. However, the effect of ventricular pacing on RV function has not been well established. We evaluated RV function in patients undergoing long-term RV pacing.Eighty-five patients and 24 healthy controls were included. After pacemaker implantation, conventional echocardiography and strain imaging were used to analyze RV function. Strain imaging measurements included peak systolic strain and strain rate. LV function and ventricular dyssynchrony by tissue Doppler imaging (TDI) were assessed. Intra- and interobserver variabilities of TDI parameters were tested on 15 randomly selected cases.All patients were in New York Heart Association functional class I or II and percentage of ventricular pacing was 96 ± 4%. RV apical induced interventricular dyssynchrony in 49 patients (60%). LV dyssynchrony was found in 51 patients (60%), when the parameter examined was the standard deviation of the time to peak myocardial systolic velocity of all 12 segments greater than 34 ms. Likewise, septal-to-lateral delay ≥ 65 ms was found in 31 patients (36%). All echocardiographic indexes of RV function were similar between patients and controls (strain: -22.8 ± 5.8% vs -22.1 ± 5.6%, P = 0.630; strain rate: -1.47 ± 0.91 s(-1) vs -1.42 ± 0.39 s(-1) , P = 0.702). Intra- and interobserver variability for RV strain was 3.1% and 5.3%, and strain rate was 1.3% and 2.1%, respectively.In patients with standard pacing indications, RV apical pacing did not seem to affect RV systolic function, despite induction of electromechanical dyssynchrony.
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- 2010
195. CCN2/CTGF silencing blocks cell aggregation in embryonal carcinoma P19 cell
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Juliana M. Coelho-Aguiar, José G. Abreu, and Diego Pinheiro Aguiar
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Pathology ,medicine.medical_specialty ,Embryonal Carcinoma Stem Cells ,Physiology ,Cell Survival ,medicine.medical_treatment ,Immunology ,Cell ,Biophysics ,Biology ,Biochemistry ,Embryonal carcinoma ,Extracellular matrix ,Cell Line, Tumor ,medicine ,Cell Adhesion ,Humans ,General Pharmacology, Toxicology and Pharmaceutics ,Cell Aggregation ,Cell Proliferation ,integumentary system ,General Neuroscience ,Growth factor ,Connective Tissue Growth Factor ,Cell Biology ,General Medicine ,medicine.disease ,Embryonic stem cell ,Cell aggregation ,Cell biology ,CTGF ,P19 cell ,medicine.anatomical_structure - Abstract
Connective tissue growth factor (CCN2/CTGF) is a matricellular-secreted protein involved in extracellular matrix remodeling. The P19 cell line is an embryonic carcinoma line widely used as a cellular model for differentiation and migration studies. In the present study, we employed an exogenous source of CCN2 and small interference RNA to address the role of CCN2 in the P19 cell aggregation phenomenon. Our data showed that increasing CCN2 protein concentrations from 0.1 to 20 nM decreased the number of cell clusters and dramatically increased cluster size without changing proliferation or cell survival, suggesting that CCN2 induced aggregation. In addition, CCN2 specific silencing inhibited typical P19 cell aggregation, which could be partially rescued by 20 nM CCN2. The present study demonstrates that CCN2 is a key molecule for cell aggregation of embryonic P19 cells.
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- 2010
196. Soybean and fish oil mixture increases IL-10, protects against DNA damage and decreases colonic inflammation in rats with dextran sulfate sodium (DSS) colitis
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Karina V. Barros, Gilclay G. Abreu, Alessandra Gambero, Patrícia de Oliveira Carvalho, Vera Lucia Flor Silveira, Roberta Araujo Navarro Xavier, Claudia Maria Oller do Nascimento, Carlos Augusto Real Martinez, and Marcelo Lima Ribeiro
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Male ,medicine.medical_specialty ,food.ingredient ,DNA damage ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Inflammation ,Biology ,Protective Agents ,Soybean oil ,chemistry.chemical_compound ,Fish Oils ,Endocrinology ,food ,Corticosterone ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Colitis ,lcsh:RC620-627 ,Peroxidase ,Biochemistry, medical ,chemistry.chemical_classification ,Research ,Dextran Sulfate ,Biochemistry (medical) ,Fish oil ,medicine.disease ,Interleukin-10 ,Rats ,Soybean Oil ,lcsh:Nutritional diseases. Deficiency diseases ,Cytokine ,chemistry ,Immunology ,Cytokines ,medicine.symptom ,DNA Damage ,Polyunsaturated fatty acid - Abstract
It was investigated whether dietary polyunsaturated fatty acids (PUFA) could influence colonic injury, tissue DNA damage, cytokines and myeloperoxidase activity (MPO) and plasma corticosterone in DSS-induced colitis rats. Male weaning Wistar rats were fed for 47 days with an AIN-93 diet with control (C), fish (F) or a mixture of fish and soybean oil (SF). The colitis was induced from day 36 until day 42 by 3% DSS in drinking water. On day 48, blood samples were collected for corticosterone determination. The distal colon was excised for histological analysis and to quantify the cytokine (IL-4, IL-10 and INF-γ), MPO and DNA damage. The disease activity index (DAI) was recorded daily during colitis induction. The DAI, MPO, histological analyses showed decreases only in the SF group compared with the C group. IL-10 was increased and DNA damage was reduced in the groups F and SF, and an inverse correlation between these variables was found. There were no differences in corticosterone, IFN-γ and IL-4 levels. Soybean and fish oil mixture may be effective in improving colonic injury and DNA damage, and it could be an important complementary therapy in UC to reduce the use of anti-inflammatory drugs and prevent colorectal cancer.
- Published
- 2010
197. Insights into the organization of dorsal spinal cord pathways from an evolutionarily conserved raldh2 intronic enhancer
- Author
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Marcelo A. Nobrega, Marianne Bronner-Fraser, Sylvia Sura-Trueba, Tatjana S Spengler, Roberta M. Cravo, Saulo H. P. de Oliveira, José G. Abreu, Jose Manuel Gonzalez, Iskra A. Signore, Karla L. Almeida, Nadia Rosenthal, Miguel L. Concha, José Xavier-Neto, Hozana A. Castillo, Alicia Colombo, Marcio Aurélio de Almeida, Esfir Slonimsky, Ana Paula Azambuja, Tiago José Pascoal Sobreira, Paulo S. L. Oliveira, and Marcos Simoes-Costa
- Subjects
Commissural Interneurons ,LIM-Homeodomain Proteins ,Retinoic acid ,Mice, Transgenic ,Tretinoin ,Biology ,ALDH1A2 ,Evolution, Molecular ,chemistry.chemical_compound ,Mice ,Interneurons ,medicine ,T Cell Transcription Factor 1 ,Animals ,Hepatocyte Nuclear Factor 1-alpha ,Enhancer ,Molecular Biology ,Transcription factor ,Research Articles ,Conserved Sequence ,Homeodomain Proteins ,Binding Sites ,Spinal cord ,Molecular biology ,Aldehyde Oxidoreductases ,Cell biology ,Repressor Proteins ,medicine.anatomical_structure ,chemistry ,nervous system ,Spinal Cord ,GDF7 ,embryonic structures ,Homeobox ,Chickens ,Developmental Biology ,Transcription Factors - Abstract
Comparative studies of the tetrapod raldh2 (aldh1a2) gene, which encodes a retinoic acid (RA) synthesis enzyme, have led to the identification of a dorsal spinal cord enhancer. Enhancer activity is directed dorsally to the roof plate and dorsal-most (dI1) interneurons through predicted Tcf- and Cdx-homeodomain binding sites and is repressed ventrally via predicted Tgif homeobox and ventral Lim-homeodomain binding sites. Raldh2 and Math1/Cath1 expression in mouse and chicken highlights a novel, transient, endogenous Raldh2 expression domain in dI1 interneurons, which give rise to ascending circuits and intraspinal commissural interneurons, suggesting roles for RA in the ontogeny of spinocerebellar and intraspinal proprioceptive circuits. Consistent with expression of raldh2 in the dorsal interneurons of tetrapods, we also found that raldh2 is expressed in dorsal interneurons throughout the agnathan spinal cord, suggesting ancestral roles for RA signaling in the ontogenesis of intraspinal proprioception.
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- 2010
198. Influence of litter layer removal on the soil thermal regime of a pine forest in a Mediterranean climate
- Author
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F. G. Abreu, M. Madeira, and José Alexandre Varanda Andrade
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Mediterranean climate ,damping depth ,soil temperature ,temperatura do solo ,Pine forest ,Soil Science ,Mineralogy ,Soil classification ,Forestry ,Fourier series ,Podzol ,Nutrient content ,séries de Fourier ,Soil temperature ,Manta morta ,pinhal ,Litter ,Environmental science ,profundidade de amortecimento ,Layer removal ,Agronomy and Crop Science - Abstract
The removal of the litter layer in Portuguese pine forests would reduce fire hazard, but on the other hand this practice would influence the thermal regime of the soil, hence affecting soil biological activity, litter decomposition and nutrient dynamics. Temperature profiles of a sandy soil (Haplic Podzol) under a pine forest were measured with thermocouples at depths to 16 cm, with and without litter layer. The litter layer acted as a thermal insulator, reducing the amplitude of the periodic temperature variation in the mineral soil underneath and increasing damping depths, particularly at low soil water contents. At the mineral soil surface the reduction of amplitudes was about 2.5 ºC in the annual cycle and 5 to 6.7 ºC in the daily cycle, depending on the soil water content. When soil was both cold and wet, mean daily soil temperatures were higher (about 1 - 1.5 ºC) under the litter layer. Improved soil thermal conditions under the litter layer recommend its retention as a forest management practice to follow in general. A remoção da manta morta nos pinhais portugueses pode reduzir o risco de incêndio florestal, mas essa prática pode influenciar o regime térmico do solo, alterando dessa forma a atividade biológica, a decomposição da manta morta e a dinâmica de nutrientes. Num solo arenoso (Haplic Podzol) sob pinus foram medidos perfis térmicos com termopares a várias profundidades até 16 cm, com ou sem manta morta. A manta morta atuou como um isolador térmico, reduzindo a amplitude da variação periódica da temperatura na camada de solo subjacente e aumentando as profundidades de amortecimento, sobretudo em teores baixos de umidade do solo. Na superfície do solo mineral a redução das amplitudes foi de cerca de 2,5 ºC no ciclo anual e de 5 a 6,7 ºC no ciclo diário, dependendo da umidade do solo. A manta morta aumentou em cerca de 1-1,5 ºC as temperaturas médias diárias do solo mineral quando este se encontrava mais frio e mais úmido. A melhoria das condições térmicas do solo sob a manta morta recomenda a sua retenção como regra a seguir enquanto prática de ordenamento florestal.
- Published
- 2010
199. Wnt/β-catenin pathway activation and myogenic differentiation are induced by cholesterol depletion
- Author
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Débora M. Portilho, Claudia Mermelstein, José G. Abreu, Manoel L. Costa, and Fabio A. Mendes
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Cancer Research ,Frizzled ,Myogenic differentiation ,Beta-catenin ,Cellular differentiation ,Muscle Fibers, Skeletal ,Chick Embryo ,Biology ,Transfection ,Models, Biological ,Animals ,Humans ,Muscle, Skeletal ,Molecular Biology ,beta Catenin ,Cell Nucleus ,Cholesterol depletion ,Myogenesis ,Cell Membrane ,beta-Cyclodextrins ,Wnt signaling pathway ,LRP6 ,Cell Differentiation ,LRP5 ,Cell Biology ,Frizzled Receptors ,Cell biology ,Wnt Proteins ,Cholesterol ,Catenin ,biology.protein ,Developmental Biology - Abstract
Myogenic differentiation is a multistep process that begins with the commitment of mononucleated precursors that withdraw from cell cycle. These myoblasts elongate while aligning to each other, guided by the recognition between their membranes. This step is followed by cell fusion and the formation of long and striated multinucleated myotubes. We have recently shown that cholesterol depletion by methyl-beta-cyclodextrin (MbetaCD) induces myogenic differentiation by enhancing myoblast recognition and fusion. Here, we further studied the signaling pathways responsible for early steps of myogenesis. As it is known that Wnt plays a role in muscle differentiation, we used the chemical MbetaCD to deplete membrane cholesterol and investigate the involvement of the Wnt/beta-catenin pathway during myogenesis. We show that cholesterol depletion promoted a significant increase in expression of beta-catenin, its nuclear translocation and activation of the Wnt pathway. Moreover, we show that the activation of the Wnt pathway after cholesterol depletion can be inhibited by the soluble protein Frzb-1. Our data suggest that membrane cholesterol is involved in Wnt/beta-catenin signaling in the early steps of myogenic differentiation.
- Published
- 2009
- Full Text
- View/download PDF
200. Tax Counts: Bringing Money-Law to LatCrit
- Author
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Alice G. Abreu
- Subjects
Social security ,Tax policy ,Labour economics ,Human rights ,media_common.quotation_subject ,Earned income tax credit ,Economics ,Redistribution of income and wealth ,Tax law ,Citizenship ,Law and economics ,Diversity (business) ,media_common - Published
- 2009
- Full Text
- View/download PDF
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